1998 Volume 1998 Issue 47 Pages 39-44
T-2 toxin, a mycotoxin produced by fungi Fusarium spp., is a potent inducer of apoptosis in human promyelotic lymphoma cell line HL-60, peripheral blood lymphocytes (PBLs) and several tissues such as thymus, spleen and liver of mice. We have previously reported that intracellular calcium ion levels play a critical role in T-2 toxin-induced apoptosis. In this research, to clarify the signal transduction pathway of T-2 toxin-induced apoptosis, we inves-tigated whether the activation of ICE family proteases (caspases) and the disruption of mitochondrial transmembrane potential (Δψm) are provoked by T-2 toxin. The activation of caspase-3, not caspase-1, was confirmed within 90 min after exposure to 100 ng/ml of T-2 toxin. Furthermore, a low concentration (6 ng/ml) of T-2 toxin-induced apoptosis was blocked by pretreating with caspase-3 inhibitor, Ac-DEVD-CHO. The disruption of Δψm was provoked within 30 to 60 min. These results indicate that the apoptotic cascade primed by T-2 toxin is mediated by a common cascade of apoptosis which is recognized in Fas and several anticancer agents.
